// compare1.c 
// gcc compare1.c

#include <stdio.h>
#include <stdlib.h>

int main()
{
    char s1[20],s2[20];
    
    printf("input s1: ");
    gets(s1);
    
    printf("input s2: ");
    gets(s2);
    
    if(s1 == s2)
        printf("s1 == s2\n");
    else
        printf("s1 != s2");
    printf("\n");
    system("pause");
    return 0;
}